First working version.

In this first version, this applicacion includes a complete CRUD using
an AJAX+JSON+REST architecture.

.gitignore

-target/
+/bin
+/target
+/assembly
+.project
+.classpath
+.settings

pom.xml

+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>es.uvigo.esei.daa</groupId>
+	<artifactId>example</artifactId>
+	<packaging>war</packaging>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>DAA Example</name>
+
+	<licenses>
+		<license>
+			<name>GNU GENERAL PUBLIC LICENSE, Version 3</name>
+			<url>http://www.gnu.org/licenses/gpl.html</url>
+			<distribution>repo</distribution>
+		</license>
+	</licenses>
+
+	<properties>
+		<maven.compiler.source>1.7</maven.compiler.source>
+		<maven.compiler.target>1.7</maven.compiler.target>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>junit</groupId>
+			<artifactId>junit</artifactId>
+			<version>4.11</version>
+			<scope>test</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.glassfish.jersey.containers</groupId>
+			<artifactId>jersey-container-servlet</artifactId>
+			<version>2.5.1</version>
+		</dependency>
+
+		<dependency>
+			<groupId>org.glassfish.jersey.media</groupId>
+			<artifactId>jersey-media-json-jackson</artifactId>
+			<version>2.5.1</version>
+		</dependency>
+
+		<dependency>
+			<groupId>mysql</groupId>
+			<artifactId>mysql-connector-java</artifactId>
+			<version>5.1.28</version>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<finalName>DAAExample</finalName>
+		<plugins>
+			<!-- Build war -->
+			<plugin>
+				<artifactId>maven-war-plugin</artifactId>
+				<groupId>org.apache.maven.plugins</groupId>
+				<version>2.1.1</version>
+				<configuration>
+					<warName>DAAExample</warName>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+</project>

src/main/java/es/uvigo/esei/daa/dao/DAO.java

+package es.uvigo.esei.daa.dao;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+
+import javax.naming.Context;
+import javax.naming.InitialContext;
+import javax.naming.NamingException;
+import javax.sql.DataSource;
+
+public abstract class DAO {
+	private final static String JNDI_NAME = "java:/comp/env/jdbc/daaexample"; 
+	
+	private final DataSource dataSource;
+	
+	public DAO() {
+		Context initContext;
+		try {
+			initContext = new InitialContext();
+			this.dataSource = (DataSource) initContext.lookup(JNDI_NAME);
+		} catch (NamingException e) {
+			throw new RuntimeException(e);
+		}
+	}
+	
+	protected Connection getConnection() throws SQLException {
+		return this.dataSource.getConnection();
+	}
+}

src/main/java/es/uvigo/esei/daa/dao/DAOException.java

+package es.uvigo.esei.daa.dao;
+
+public class DAOException extends Exception {
+	private static final long serialVersionUID = 1L;
+
+	public DAOException() {
+	}
+
+	public DAOException(String message) {
+		super(message);
+	}
+
+	public DAOException(Throwable cause) {
+		super(cause);
+	}
+
+	public DAOException(String message, Throwable cause) {
+		super(message, cause);
+	}
+
+	public DAOException(String message, Throwable cause,
+			boolean enableSuppression, boolean writableStackTrace) {
+		super(message, cause, enableSuppression, writableStackTrace);
+	}
+}

src/main/java/es/uvigo/esei/daa/dao/PeopleDAO.java

+package es.uvigo.esei.daa.dao;
+
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.LinkedList;
+import java.util.List;
+
+import es.uvigo.esei.daa.entities.Person;
+
+public class PeopleDAO extends DAO {
+	public List<Person> list() throws DAOException {
+		try (final Connection conn = this.getConnection()) {
+			try (Statement statement = conn.createStatement()) {
+				try (ResultSet result = statement.executeQuery("SELECT * FROM people")) {
+					final List<Person> people = new LinkedList<>();
+					
+					while (result.next()) {
+						people.add(new Person(
+							result.getInt("id"),
+							result.getString("name"),
+							result.getString("surname")
+						));
+					}
+					
+					return people;
+				}
+			}
+		} catch (SQLException e) {
+			throw new DAOException(e);
+		}
+	}
+	
+	public void delete(int id) throws DAOException {
+		try (final Connection conn = this.getConnection()) {
+			final String query = "DELETE FROM people WHERE id=?";
+			
+			try (PreparedStatement statement = conn.prepareStatement(query)) {
+				statement.setInt(1, id);
+				
+				if (statement.executeUpdate() != 1) {
+					throw new SQLException("Error inserting value");
+				}
+			}
+		} catch (SQLException e) {
+			throw new DAOException(e);
+		}
+	}
+	
+	public Person modify(int id, String name, String surname) throws DAOException {
+		try (final Connection conn = this.getConnection()) {
+			final String query = "UPDATE people SET name=?, surname=? WHERE id=?";
+			
+			try (PreparedStatement statement = conn.prepareStatement(query)) {
+				statement.setString(1, name);
+				statement.setString(2, surname);
+				statement.setInt(3, id);
+				
+				if (statement.executeUpdate() == 1) {
+					return new Person(id, name, surname); 
+				} else {
+					throw new SQLException("Error inserting value");
+				}
+			}
+		} catch (SQLException e) {
+			throw new DAOException();
+		}
+	}
+	
+	public Person add(String name, String surname) throws DAOException {
+		try (final Connection conn = this.getConnection()) {
+			final String query = "INSERT INTO people VALUES(null, ?, ?)";
+			
+			try (PreparedStatement statement = conn.prepareStatement(query, Statement.RETURN_GENERATED_KEYS)) {
+				statement.setString(1, name);
+				statement.setString(2, surname);
+				
+				if (statement.executeUpdate() == 1) {
+					try (ResultSet resultKeys = statement.getGeneratedKeys()) {
+						if (resultKeys.next()) {
+							return new Person(resultKeys.getInt(1), name, surname);
+						} else {
+							throw new SQLException("Error retrieving inserted id");
+						}
+					}
+				} else {
+					throw new SQLException("Error inserting value");
+				}
+			}
+		} catch (SQLException e) {
+			throw new DAOException(e);
+		}
+	}
+}

src/main/java/es/uvigo/esei/daa/entities/Person.java

+package es.uvigo.esei.daa.entities;
+
+public class Person {
+	private int id;
+	private String name;
+	private String surname;
+	
+	public Person(int id, String name, String surname) {
+		this.id = id;
+		this.name = name;
+		this.surname = surname;
+	}
+	
+	public int getId() {
+		return id;
+	}
+
+	public void setId(int id) {
+		this.id = id;
+	}
+
+	public String getName() {
+		return name;
+	}
+
+	public void setName(String name) {
+		this.name = name;
+	}
+
+	public String getSurname() {
+		return surname;
+	}
+
+	public void setSurname(String surname) {
+		this.surname = surname;
+	}
+}

src/main/java/es/uvigo/esei/daa/rest/People.java

+package es.uvigo.esei.daa.rest;
+
+import javax.ws.rs.GET;
+import javax.ws.rs.Path;
+import javax.ws.rs.Produces;
+import javax.ws.rs.QueryParam;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+
+import es.uvigo.esei.daa.dao.DAOException;
+import es.uvigo.esei.daa.dao.PeopleDAO;
+
+@Path("/people")
+@Produces(MediaType.APPLICATION_JSON)
+public class People {
+	private final PeopleDAO dao;
+	
+	public People() {
+		this.dao = new PeopleDAO();
+	}
+
+	@GET
+	@Path("/list")
+	public Response list() {
+		try {
+			return Response.ok(this.dao.list(), MediaType.APPLICATION_JSON).build();
+		} catch (DAOException e) {
+			e.printStackTrace();
+			return Response.serverError().entity(e.getMessage()).build();
+		}
+	}
+
+	@GET
+	@Path("/delete")
+	public Response delete(
+		@QueryParam("id") int id
+	) {
+		try {
+			this.dao.delete(id);
+			
+			return Response.ok(id).build();
+		} catch (DAOException e) {
+			e.printStackTrace();
+			return Response.serverError().entity(e.getMessage()).build();
+		}
+	}
+	
+	@GET
+	@Path("/modify")
+	public Response modify(
+		@QueryParam("id") int id, 
+		@QueryParam("name") String name, 
+		@QueryParam("surname") String surname
+	) {
+		try {
+			return Response.ok(this.dao.modify(id, name, surname)).build();
+		} catch (DAOException e) {
+			e.printStackTrace();
+			return Response.serverError().entity(e.getMessage()).build();
+		}
+	}
+	
+	@GET
+	@Path("/add")
+	public Response add(
+		@QueryParam("name") String name, 
+		@QueryParam("surname") String surname
+	) {
+		try {
+			return Response.ok(this.dao.add(name, surname)).build();
+		} catch (DAOException e) {
+			e.printStackTrace();
+			return Response.serverError().entity(e.getMessage()).build();
+		}
+	}
+}

src/main/webapp/META-INF/MANIFEST.MF

+Manifest-Version: 1.0
+Class-Path: 
+

src/main/webapp/META-INF/context.xml

+<Context>
+	<!-- maxActive: Maximum number of database connections in pool. Make sure 
+		you configure your mysqld max_connections large enough to handle all of your 
+		db connections. Set to -1 for no limit. -->
+
+	<!-- maxIdle: Maximum number of idle database connections to retain in pool. 
+		Set to -1 for no limit. See also the DBCP documentation on this and the minEvictableIdleTimeMillis 
+		configuration parameter. -->
+
+	<!-- maxWait: Maximum time to wait for a database connection to become available 
+		in ms, in this example 10 seconds. An Exception is thrown if this timeout 
+		is exceeded. Set to -1 to wait indefinitely. -->
+
+	<!-- username and password: MySQL username and password for database connections -->
+
+	<!-- driverClassName: Class name for the old mm.mysql JDBC driver is org.gjt.mm.mysql.Driver 
+		- we recommend using Connector/J though. Class name for the official MySQL 
+		Connector/J driver is com.mysql.jdbc.Driver. -->
+
+	<!-- url: The JDBC connection url for connecting to your MySQL database. -->
+
+	<Resource name="jdbc/daaexample" auth="Container" type="javax.sql.DataSource"
+		maxActive="100" maxIdle="30" maxWait="10000" username="daa" password="daa"
+		driverClassName="com.mysql.jdbc.Driver" url="jdbc:mysql://localhost:3306/daaexample" />
+</Context>
\ No newline at end of file

src/main/webapp/WEB-INF/web.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
+  <display-name>DAAExampleTMP</display-name>
+  <welcome-file-list>
+    <welcome-file>index.html</welcome-file>
+    <welcome-file>index.htm</welcome-file>
+    <welcome-file>index.jsp</welcome-file>
+    <welcome-file>default.html</welcome-file>
+    <welcome-file>default.htm</welcome-file>
+    <welcome-file>default.jsp</welcome-file>
+  </welcome-file-list>
+  <resource-ref>
+    <description>DAA Example DB Connection</description>
+    <res-ref-name>jdbc/daaexample</res-ref-name>
+    <res-type>javax.sql.DataSource</res-type>
+    <res-auth>Container</res-auth>
+  </resource-ref>
+  <servlet>
+    <servlet-name>javax.ws.rs.core.Application</servlet-name>
+  </servlet>
+  <servlet-mapping>
+    <servlet-name>javax.ws.rs.core.Application</servlet-name>
+    <url-pattern>/rest/*</url-pattern>
+  </servlet-mapping>
+</web-app>
\ No newline at end of file

src/main/webapp/index.html

+<!DOCTYPE html>
+<html>
+<head>
+<meta charset="UTF-8">
+<title>DAA Example</title>
+</head>
+<body>
+	<div id="people-container">
+		<h1>People</h1>
+	</div>
+
+	<script type="text/javascript" src="http://code.jquery.com/jquery-2.1.0.js"></script>
+	<script type="text/javascript" src="js/view/people.js"></script>
+	<script type="text/javascript">
+		$(document).ready(function() {
+			insertPeopleForm($('#people-container'));
+			insertPeopleList($('#people-container'));
+			initPeople();
+		});
+	</script>
+</body>
+</html>
\ No newline at end of file

src/main/webapp/js/dao/people.js

+function listPeople(done, fail, always) {
+	done = typeof done !== 'undefined' ? done : function() {};
+	fail = typeof fail !== 'undefined' ? fail : function() {};
+	always = typeof always !== 'undefined' ? always : function() {};
+	
+	$.getJSON('rest/people/list')
+		.done(done)
+		.fail(fail)
+		.always(always);
+}
+
+function addPerson(person, done, fail, always) {
+	done = typeof done !== 'undefined' ? done : function() {};
+	fail = typeof fail !== 'undefined' ? fail : function() {};
+	always = typeof always !== 'undefined' ? always : function() {};
+	
+	$.getJSON('rest/people/add', person)
+		.done(done)
+		.fail(fail)
+		.always(always);
+}
+
+function modifyPerson(person, done, fail, always) {
+	done = typeof done !== 'undefined' ? done : function() {};
+	fail = typeof fail !== 'undefined' ? fail : function() {};
+	always = typeof always !== 'undefined' ? always : function() {};
+	
+	$.getJSON('rest/people/modify', person)
+		.done(done)
+		.fail(fail)
+		.always(always);
+}
+
+function deletePerson(id, done, fail, always) {
+	done = typeof done !== 'undefined' ? done : function() {};
+	fail = typeof fail !== 'undefined' ? fail : function() {};
+	always = typeof always !== 'undefined' ? always : function() {};
+	
+	$.getJSON('rest/people/delete', { 'id': id })
+		.done(done)
+		.fail(fail)
+		.always(always);
+}
\ No newline at end of file

src/main/webapp/js/view/people.js

+var peopleFormId = 'people-form';
+var peopleListId = 'people-list';
+var peopleFormQuery = '#' + peopleFormId;
+var peopleListQuery = '#' + peopleListId;
+
+function insertPeopleList(parent) {
+	parent.append(
+		'<table id="' + peopleListId + '">\
+			<tr>\
+				<th>Nombre</th>\
+				<th>Apellido</th>\
+				<th></th>\
+				<th></th>\
+			</tr>\
+		</table>'
+	);
+}
+
+function insertPeopleForm(parent) {
+	parent.append(
+		'<form id="' + peopleFormId + '">\
+			<input name="id" type="hidden" value=""/>\
+			<input name="name" type="text" value="" />\
+			<input name="surname" type="text" value=""/>\
+			<input id="btnSubmit" type="submit" value="Create"/>\
+			<input id="btnClear" type="reset" value="Limpiar"/>\
+		</form>'
+	);
+}
+
+function createPersonRow(person) {
+	return '<tr id="person-'+ person.id +'">\
+		<td class="name">' + person.name + '</td>\
+		<td class="surname">' + person.surname + '</td>\
+		<td>\
+			<a class="edit" href="#">Edit</a>\
+		</td>\
+		<td>\
+			<a class="delete" href="#">Delete</a>\
+		</td>\
+	</tr>';
+}
+
+function formToPerson() {
+	var form = $(peopleFormQuery);
+	return {
+		'id': form.find('input[name="id"]').val(),
+		'name': form.find('input[name="name"]').val(),
+		'surname': form.find('input[name="surname"]').val()
+	};
+}
+
+function rowToPerson(id) {
+	var row = $('#person-' + id);
+
+	return {
+		'id': id,
+		'name': row.find('td.name').text(),
+		'surname': row.find('td.surname').text()
+	};
+}
+
+function personToForm(person) {
+	var form = $(peopleFormQuery);
+	form.find('input[name="id"]').val(person.id);
+	form.find('input[name="name"]').val(person.name);
+	form.find('input[name="surname"]').val(person.surname);
+}
+
+function isEditing() {
+	return $(peopleFormQuery + ' input[name="id"]').val() != "";
+}
+
+function disableForm() {
+	$(peopleFormQuery + ' input').prop('disabled', true);
+}
+
+function enableForm() {
+	$(peopleFormQuery + ' input').prop('disabled', false);
+}
+
+function showErrorMessage(jqxhr, textStatus, error) {
+	alert(textStatus + ": " + error);
+}
+
+function resetForm() {
+	$(peopleFormQuery)[0].reset();
+	$(peopleFormQuery + ' input[name="id"]').val('');
+	$('#btnSubmit').val('Crear');
+}
+
+function addRowListeners(person) {
+	$('#person-' + person.id + ' a.edit').click(function() {
+		personToForm(rowToPerson(person.id));
+		$('input#btnSubmit').val('Modificar');
+	});
+	$('#person-' + person.id + ' a.delete').click(function() {
+		if (confirm('Está a punto de eliminar a una persona. ¿Está seguro de que desea continuar?')) {
+			deletePerson(person.id,
+				function() {
+					$('tr#person-' + person.id).remove();
+				},
+				showErrorMessage
+			);
+		}
+	});
+}
+
+function appendToTable(person) {
+	$(peopleListQuery + ' > tbody:last')
+		.append(createPersonRow(person));
+	addRowListeners(person);
+}
+
+function initPeople() {
+	$.getScript('js/dao/people.js', function() {
+		listPeople(function(people) {
+			$.each(people, function(key, person) {
+				appendToTable(person);
+			});
+		});
+		
+		$(peopleFormQuery).submit(function(event) {
+			var person = formToPerson();
+			
+			if (isEditing()) {
+				modifyPerson(person,
+					function(person) {
+						$('#person-' + person.id + ' td.name').text(person.name);
+						$('#person-' + person.id + ' td.surname').text(person.surname);
+						resetForm();
+					},
+					showErrorMessage,
+					enableForm
+				);
+			} else {
+				addPerson(person,
+					function(person) {
+						appendToTable(person);
+						resetForm();
+					},
+					showErrorMessage,
+					enableForm
+				);
+			}
+			
+			return false;
+		});
+		
+		$('#btnClear').click(resetForm);
+	});
+};